[PATCH] fix-glamofb-flicker-72hz-refresh.patch

[Andy Green]

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Somebody in the thread at some point said:

> See last 4 lines (DSU, DHO, Note1&2)! As well as PCLKL & PCLKH! We are running 
> LCM out of specs for at least 6 parameters - with 24Mhz PCLK.

Funnily enough this doesn't seem to actually make the current problem or
any problem AFAIK despite it is pretty wild.

> With this R-C combination the square wave is integrated to make an 
> astonishingly linear (probably that's L, not R) triangular wave, with 

Yes I think these "resistor arrays" are all these

http://www.acxc.com.tw/product/fa2012/FA2012-KR40PAA_070827.pdf

Interestingly GTA01 did not have this 47pF cap at least on the 01B-A4.

> For my opinion, there MUST NOT be any R-C in any of the bus lines, because it 
> introduces propagation delay (or better: phase shift). Even with a C a 
> magnitude smaller, there still is no simple way to program glamo LCD I/F 
> timing correctly. 

Well it depends on the relationship between the delays on the bus and
the clock it is synchronized with.  There is always R, L and C on a bus
just from the PCB and the tracking and what it is routed near after all.
 Arriving at the same time isn't the problem, so long as they all arrive
respecting the setup time from the clock.

> My suggestion: make that C a NC (the good news: doesn't need a PCB redesign). 
> Whatever might have been the reason for introducing it, find another 
> solution.

If it was there for emissions control then we should better propose to
reduce it rather than eliminate it... after all we are working without
symptoms with that crazy clock, if we make it many times better that's
margin for us, and the guy responsible for standards compliance can
still sleep nights.  But still we better confirm it by rework, in case
the situation actually is it only works at all because of the phase
shift introduced by this network :-)

- -Andy
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